Ask Mr. Smarty Plants

On the subject of plants for pots, first read our How-To Article on Container Gardens for Native Plants. Then, see this previous Mr. Smarty Plants answer on that subject. While this question was from Austin, there is not that much difference in the climates between here and North Central Texas, and certainly the advice on choosing the plants applies. 

If everything died after constant watering, it may not have been the plants, it may have been the dirt. Before you spend any more time and money on plants this year, first do a little work in preparing the beds. In your area of North Central Texas you probably have a whole lot of clay in your soil. If that is true and you were watering a lot, you may have drowned the roots of your plants. Plants native to your area (which is what we at the Lady Bird Johnson Wildflower Center recommend) would ordinarily be able to tolerate low watering practices, and certainly would object to too much water. Whatever your soils are, they certainly will benefit with the application of some compost or other organic materials. If you don't have a compost pile, you can buy it in bags at the nurseries. Work it into your soil, turning it over, aerating the soil while you amend it. Here is an excellent article from About.com: Organic Gardening Understanding and Improving Clay Soil.

The next step is choosing the right plants for the right spots. You say you have "sunny and shady" flower beds; so which is it? You need to watch your beds for a day, keeping track of what portions have sun (6 or more hours of sun a day), part shade (2 to 6 hours of sun) or shade (less than 2 hours of sun). To help you in making some appropriate selections, we will go to our Recommended Species, click on North Central Texas on the map. In the NARROW YOUR SEARCH section on that page you will have a number of options to select. We'll do a trial run, and then you can go from there. First, we'll select "herbs" (herbaceous blooming plants) from General Appearance, then "perennial" from Lifespan, and "part shade" from Light Requirements. This search gave us 16 choices, from which we chose 8 as examples. You can follow each plant link to learn when the plant blooms, what colors, how high and what kind of water use it has. You may note that many of these plants will tolerate more than one level of light; in fact, some may say "Sun, part shade or shade" in the Light Requirements line, which gives you some latitude in placement of those plants. Most blooming plants will bloom better in more sun.

After you have practiced on this, go back to Recommended Species, again check on North Central Texas, and search on other characteristics, like "shrub" or "sun" or "annual." For blooming plants you can even enter the color blooms you want and the months you want them to bloom. You may not get any results from a search that narrow, but you might.

North Central Texas Garden Plants: 

Aquilegia canadensis (red columbine)

Asclepias tuberosa (butterfly milkweed)

Conoclinium coelestinum (blue mistflower)

Echinacea purpurea (eastern purple coneflower)

Lobelia cardinalis (cardinalflower)

Melampodium leucanthum (plains blackfoot)

Salvia azurea (azure blue sage)

Salvia roemeriana (cedar sage)

From Our Native Plant Image Gallery:

Aquilegia canadensis

Asclepias tuberosa

Conoclinium coelestinum

Echinacea purpurea

Lobelia cardinalis

Melampodium leucanthum

Salvia azurea

Salvia roemeriana